<script src="../../resources/testharness.js"></script>
<script src="../../resources/testharnessreport.js"></script>
<body>
<script>
async_test(t => {
    // Create auxiliary canvas to draw to and create an image from.
    // This is done instead of simply loading an image from the file system
    // because that would throw a SECURITY_ERR DOM Exception.
    var aCanvas = document.createElement('canvas');
    aCanvas.width = aCanvas.height = 10;
    var aCtx = aCanvas.getContext('2d');
    aCtx.fillStyle = 'rgba(0, 0, 255, 1)';
    aCtx.fillRect(0, 0, 50, 50);
    
    // Create the image object to be drawn on the master canvas.
    var img = new Image();
    img.onload = drawImageToCanvasAndCheckPixels;
    img.src = aCanvas.toDataURL(); // set a data URI of the base64 encoded image as the source
    
    aCanvas.width = 10;
    aCtx.fillStyle = 'rgba(0, 0, 255, 0.5)';
    aCtx.fillRect(0, 0, 50, 50);
    // Create the image object to be drawn on the master canvas.
    var transparentImg = new Image();
    transparentImg.onload = drawImageToCanvasAndCheckPixels;
    transparentImg.src = aCanvas.toDataURL(); // set a data URI of the base64 encoded image as the source
    
    // Create master canvas.
    var canvas = document.createElement('canvas');
    document.body.appendChild(canvas);
    canvas.width = 150;
    canvas.height = 110;
    var ctx = canvas.getContext('2d');
    
    function testPixelShadow(x, y, color)
    {
        assert_array_equals(ctx.getImageData(x, y, 1, 1).data, color);
    }
    
    function testPixelShadowAlpha(x, y, color)
    {
        var data = ctx.getImageData(x, y, 1, 1).data;
        assert_array_equals(data.slice(0,3), color.slice(0,3));
        assert_approx_equals(data[3], color[3], 10);
    }
    
    var testPixelShadowScenarios = [
        ['Verify solid shadow 1', 40, 40, [255, 0, 0, 255]],
        ['Verify solid shadow 2', 59, 59, [255, 0, 0, 255]],
    ];
    
    var testPixelShadowAlphaScenarios = [
        ['Verify solid alpha shadow 1', 41, 81, [255, 0, 0, 76]],
        ['Verify solid alpha shadow 2', 59, 99, [255, 0, 0, 76]],
    
        ['Verify blurry shadow 1', 90, 39, [255, 0, 0, 114]],
        ['Verify blurry shadow 2', 90, 60, [255, 0, 0, 114]],
        ['Verify blurry shadow 3', 79, 50, [255, 0, 0, 114]],
        ['Verify blurry shadow 4', 100, 50, [255, 0, 0, 114]],
    
        ['Verify blurry alpha shadow 1', 90, 79, [255, 0, 0, 34]],
        ['Verify blurry alpha shadow 2', 90, 100, [255, 0, 0, 34]],
        ['Verify blurry alpha shadow 3', 79, 90, [255, 0, 0, 34]],
        ['Verify blurry alpha shadow 4', 100, 90, [255, 0, 0, 34]],
        
        ['Verify blurry shadow of image with alpha 1', 130, 39, [255, 0, 0, 57]],
        ['Verify blurry shadow of image with alpha 2', 130, 60, [255, 0, 0, 57]],
        ['Verify blurry shadow of image with alpha 3', 119, 50, [255, 0, 0, 57]],
        ['Verify blurry shadow of image with alpha 4', 140, 50, [255, 0, 0, 57]],
    
        ['Verify blurry alpha shadow of image with alpha 1', 130, 79, [255, 0, 0, 17]],
        ['Verify blurry alpha shadow of image with alpha 2', 130, 100, [255, 0, 0, 17]],
        ['Verify blurry alpha shadow of image with alpha 3', 119, 90, [255, 0, 0, 17]],
        ['Verify blurry alpha shadow of image with alpha 4', 140, 90, [255, 0, 0, 17]],
    ];
    
    var imagesLoaded = 0;
    function drawImageToCanvasAndCheckPixels() {
        imagesLoaded = imagesLoaded + 1;
        if (imagesLoaded == 2) {
            ctx.scale(2, 2);
            ctx.shadowOffsetX = 20;
            ctx.shadowOffsetY = 20;
            ctx.fillStyle = 'rgba(0, 0, 255, 1)';
    
            ctx.shadowColor = 'rgba(255, 0, 0, 1.0)';
            ctx.drawImage(img, 10, 10);
    
            ctx.shadowColor = 'rgba(255, 0, 0, 0.3)';
            ctx.drawImage(img, 10, 30);
    
            ctx.shadowColor = 'rgba(255, 0, 0, 1.0)';
            ctx.shadowBlur = 10;
            ctx.drawImage(img, 30, 10);
    
            ctx.shadowColor = 'rgba(255, 0, 0, 0.3)';
            ctx.drawImage(img, 30, 30);
    
            ctx.shadowColor = 'rgba(255, 0, 0, 1.0)';
            ctx.drawImage(transparentImg, 50, 10);
    
            ctx.shadowColor = 'rgba(255, 0, 0, 0.3)';
            ctx.drawImage(transparentImg, 50, 30);
            
            t.step(runTests);
            t.done();
    
        }
    }
    
    function runTests() {
        for (var i = 0; i < testPixelShadowScenarios.length; i++)
            testPixelShadow(testPixelShadowScenarios[i][1],
                            testPixelShadowScenarios[i][2],
                            testPixelShadowScenarios[i][3]);
    
        for (var i = 0; i < testPixelShadowAlphaScenarios.length; i++)
            testPixelShadowAlpha(testPixelShadowAlphaScenarios[i][1],
                                 testPixelShadowAlphaScenarios[i][2],
                                 testPixelShadowAlphaScenarios[i][3]);
    }

}, 'Ensure correct behavior of canvas with drawImage+shadow after scaling. A blue and red checkered pattern should be displayed.');
</script>
</body>
